How do I know whether the travel motor or the swivel joint is faulty?

A swivel (centre joint) fault usually affects functions beyond travel — weak swing, drift, oil weeping from the joint — while a travel motor fault is normally limited to tracking behaviour on one or both sides. Pressure testing at the travel circuit separates them properly, and a machine that travels weakly on both sides points at the pump or the control valve rather than two motors failing together.

Is it worth rebuilding a travel motor instead of replacing it?

On a motor with a sound housing, a rebuild with new seals, pistons, valve plate and bearings is often the economical route and restores normal performance. When the housing, shaft splines or the reduction gear set are damaged, replacement is the better decision. Either way, the failed motor contaminates the hydraulic circuit, so the oil and filters must be changed at the same time.

Kobelco SK200-8 Travel Motor: Final Drive Failure Signs, Rebuild or Replace

Q: Which travel motor does a Kobelco SK200-8 use?

SK200-8 class machines are normally fitted with a two-speed travel motor of the Nabtesco GM38VB class, quoted under Kobelco assembly numbers YN15V00037F1, YN15V00037F2 and YN15V00037F3, with an integral planetary reduction gear and a parking brake. The later GM38VC unit used on SK200-10 and SK220XD-10 class machines is quoted under assembly number YN15V00083F1 and is not interchangeable with it. Build and market variant can change the exact assembly, so the nameplate on the travel motor and the machine serial number should always be confirmed before ordering. Guangzhou Shenyue Machinery Technology Co., Ltd. identifies travel motors from a nameplate photograph at no charge.

Product Guide · September 23, 2026 · Guangzhou, China

Kobelco SK200-8 Travel Motor & Final Drive Guide

When a 20-tonne machine stops tracking straight, the travel motor is usually blamed first and diagnosed last. Travel faults actually divide three ways — hydraulic, electrical and mechanical — and a final drive condemned without a diagnosis is an expensive way to find out which one you had. Corbay is the international export brand of Guangzhou Shenyue Machinery Technology Co., Ltd., Guangzhou, China. Travel motors and final drives are among the assemblies we quote most often, and this guide is that conversation.

Which Travel Motor Does a Kobelco SK200-8 Use?

A SK200-8 class machine normally carries a two-speed travel motor of the Nabtesco GM38VB class, with an integral planetary reduction gear and a spring-applied, hydraulically released parking brake. The two-speed function is switched hydraulically — the small solenoid and valve that control it live upstream, not inside the motor, which is precisely why so many "motor" faults turn out to be electrical.

Generation is the single most common source of a wrong travel motor order. The GM38VB is the travel motor family fitted to the SK200-8 generation and is quoted under Kobelco assembly numbers YN15V00037F1, YN15V00037F2 and YN15V00037F3. The GM38VC is the later unit used on SK200-10 and SK220XD-10 class machines, quoted under assembly number YN15V00083F1. The two assemblies are not interchangeable, so the assembly number or a sharp photograph of the nameplate is the only reliable way to order the correct one — see our GM38VB travel motor page for the format we quote from.

Hydraulic components on Kobelco machines have long come from the same Japanese supplier ecosystem, with Kawasaki supplying much of the pump and motor technology used across the industry. The practical consequence for a buyer is good news: these assemblies are well documented and widely supported by the aftermarket. It also means the nameplate is the authority — the assembly number on the motor, not the machine model name, is what a supplier should quote from.

Six Travel Symptoms — and What Each One Points At

No travel on one side.Motor, travel brake, the travel spool in the control valve, or the travel pilot circuit. A brake that will not release feels exactly like a dead motor from the cab.

Weak travel on both sides.Almost never two failed motors at once. Look at main pump delivery, relief settings and the travel straight-travel valve first.

Slow, noisy final drive with metal in the oil.The clearest mechanical signal there is — gear or bearing damage inside the reduction gear. Magnetic plugs and drained oil tell the story.

Machine drifts on a slope with the lever centred.Brake or counter-balance valve wear, not a loss of motive power.

Two-speed will not switch.Usually the solenoid, the switch or the wiring. Confirm the pilot pressure before touching the motor.

Oil weeping from the motor body or the joint between motor and gearbox.Seal failure, and the beginning of oil loss and contamination. On a tracked machine this failure mode quietly destroys the motor if it is left.

Diagnose Before You Condemn: Three Systems, One Symptom

Our technical team — each with more than ten years on Kobelco and HINO parts — applies the same sequence to every travel complaint, and it costs a fraction of a new assembly:

Hydraulic.Measure travel circuit pressure against specification, check the relief and travel spools, and confirm correct pilot pressure at both motors. A worn travel spool mimics motor failure convincingly.

Electrical.Two-speed selection, travel pressure sensors and the wiring to them. Sensor faults on these machines are far more common than internal motor failure, and they are also far cheaper.

Mechanical.Drain the gear oil and inspect it. Fresh-looking oil with no metal, a motor body that stays cool, and no abnormal noise argue strongly for a hydraulic or electrical cause. Metal, heat and noise argue for the gearbox.

A swivel or centre joint problem also presents as weak travel, and it is regularly missed. If swing is weak at the same time, or if oil is visible around the joint, treat the joint as a suspect before ordering a motor — Guangzhou Shenyue Machinery Technology Co., Ltd. quotes the full travel and swing circuit, which makes it easier to test one item against another.

Rebuild, Replace or Reconditioned?

Once the motor is genuinely at fault, the decision is arithmetic rather than preference:

Rebuild when the housing, shaft and splines are sound: new seals, pistons, valve plate and bearings restore performance at a fraction of the price of an assembly.

Replace when the housing is scored, the shaft or splines are worn, or the reduction gear set has failed. A rebuilt unit on a damaged core is money recycled into a second failure.

Reconditioned is a legitimate third option on expensive assemblies — a used core rebuilt to specification with the critical surfaces renewed. It must always be quoted as reconditioned, never sold as new, and the grade belongs on the quotation.

Whatever the route, one rule is not negotiable: a failed travel motor has already contaminated the hydraulic circuit. Metallic particles from a failing unit circulate through the pump, the valve block and the cylinders. Change the oil, change the filters, and flush before the replacement runs. Skipping that step is the single most common reason a new motor fails inside its first hundred hours.

Seals and bearings inside a travel motor are where cheap parts punish hardest. NOK seals in the rotating group and known-quality bearings are the difference between a rebuild that lasts and one that comes back, and we stock both for the assemblies we supply.

What We Need to Quote a Travel Motor

Nameplate photograph of the travel motor.Assembly number and maker, in focus. This is the single most useful item.

Machine model and serial number.SK200-8, SK210LC-8 and SK200-8S vary in build details that matter here.

Which parts are affected.One side or both, and whether the symptom appears in travel only.

The state of the drained oil.Metal, water or burnt smell changes the recommendation between rebuild and replace.

Grade preference.Genuine, OEM-quality, aftermarket or reconditioned — all four are quoted with the grade stated line by line, and we will say plainly when the cheaper line is false economy.

Kobelco SK200-8 Travel Motor — FAQ

Do you supply the reduction gear separately?Yes — gear sets, bearings, seals, brake components and complete motor-and-gearbox assemblies are all quoted from the nameplate number.

Can a travel motor be identified without a number?Yes. Send photographs of the motor, the housing and the machine data plate, and our team will narrow it to the correct assembly and confirm before you commit.

How fast can a travel motor ship?Common references are held in stock and normally move by air express within days; unusual builds are confirmed with an honest lead time rather than a promise.

Send the Nameplate, Not Just the Model

Send the travel motor nameplate and the machine details, and our technical team at Guangzhou Shenyue Machinery Technology Co., Ltd. will confirm what fits, what grade each option is, and what it will cost to get it moving. Identification is free, whether or not you order.

Browse Travel Motors Send a Travel Motor Nameplate

Corbay Excavator Parts is the international export brand of Shenyue Machinery (Guangzhou Shenyue Machinery Technology Co., Ltd.), Guangzhou, China. Shenyue is an independent parts specialist and is not affiliated with, or an authorized dealer of, Kobelco Limited. Parts are supplied as genuine, OEM or clearly identified aftermarket items, and the grade is stated on every quotation.